1. Field of the Invention
The present invention relates generally to archery products and more particularly to mechanical broadhead arrow tips.
2. Related Art
Many mechanical broadhead arrow tips have movable blades that can be stowed during flight and deploy upon impact. The blades are stowed during flight to provide aerodynamic stability to the arrow during flight. Upon impact the blades are deployed to an extended position that enlarges the cutting profile of the arrow tip.
Some mechanical broadhead arrow tips use an expendable retention device to retain the movable blades in the stowed position. Such expendable retention devices usually need to be replaced after each use of the arrow. For example, some broadheads use an elastomeric o-ring that that stretches around the outside of the arrowhead and exerts a resistive force against the blades to hold the blades in the stowed position. When the arrow impacts its target the impact can cause the blades to cut the o-ring so that the blades can pivot into the extended position.
Unfortunately, broadhead arrow tips using such expendable retention devices can cause a number of problems for avid archers. For example, the retention devices can fail prematurely due to operating conditions such as environmental exposure, extreme velocities of the arrows, and the like. It will be appreciated that premature failure of the retention device can cause aerodynamic problems for the arrow in flight, which may result in target loss, non-lethal wounding of prey and laceration hazards to the archer. Moreover, expendable retention devices need to be replaced after every use which increases the costs and decreases the efficiency of the broadhead to the archer.
Another problem of many broadhead arrow tips is they have multiple moving parts that can cause balance and aerodynamic problems for the arrow in flight. Additionally, having many moving components in one arrow tip generally increases the amount of kinetic energy needed in order to deploy the blades. Using kinetic energy to deploy the blades reduces the amount of energy available to the arrow for penetrating a target. Moreover, many moving parts can increase the overall manufacturing costs of the arrow.
Yet another problem with some mechanical broadhead arrow tips is that the blades can vibrate during flight which can cause a whistling noise as the arrow flies. Such noises have been known to startle animals, causing them to bolt and leaving the bow hunter without a kill.